Dominant species spread across the globe are just as vulnerable during a mass extinction event as more fragile ones confined to a single locale, according to a study published Tuesday. As Earth enters the sixth such concentrated annihilation of life over the last half-billion years, this could be bad news for humans, the researchers say. The last major wipeout occurred 66 million years ago when a giant asteroid put a relatively quick end to the age of dinosaurs after their spectacular 150 million-year run. By comparison, humans have been around for about one tenth of one percent of that time. Outside of these moments of planetary upheaval — each of which decimated 50 to 95 percent of life forms — species tend to disappear at a steady ‘background’ rate that has varied remarkably little. During the previous big five extinction, however, that rate increased by at least 100-fold. And that’s about

Read More: During mass extinction, no species safe: Study by professor at the University of Leeds